Cashew apples, tropical pseudo fruit, are rich in bioactive compounds. It is still underutilized due to its high perishability and its astringent flavor. This study aims to extend its shelf life by chemical dip and dry method at the rural level. Inhibition of fruit-spoiling enzymes, such as polyphenol oxidase (PPO), peroxidase (POD), amylase, and cellulase, was a significant response in this method. Enzyme inhibition was carried out using chemicals: NaCl (1-10mM), CaCl2 (1-10mM), and ethylenediamine tetraacetic acid (0.1-1mM). The effect of chemical concentration and dipping time was studied using a full factorial method at three levels (-1, 0, and 1). The dipping time ranged from 60 to 180min, and chemical concentrations from 1 to 10mM were studied. Optimal treatment conditions were obtained as follows: NaCl concentration of 9.45mM, dipping time of 160min, and CaCl2 concentration of 7.8mM, dipping time of 160min. NaCl pretreatment showed maximum inhibition of PPO (>80%) and POD (>80%), whereas CaCl2 pretreatment showed maximum inhibition of amylase (60.58%) and cellulase (80.23%). Hence, to avoid postharvest losses, pretreatment with NaCl and CaCl2 was adequate to preserve the texture and color of cashew apples. PRACTICAL APPLICATION: Chemical pretreatment can prevent the postharvest losses of cashew apples. Inhibition of PPO, POD, amylase, and cellulase is vital in the shelf-life extension of cashew apples. Sodium chloride dip is a cost-effective method for increasing the storability of cashew apples.
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